Synthesis Of Phenanthrene Derivatives And Their Applications In Asymmetric Catalysis

The synthesis of chiral ligands(or catalysts) is a very important part in the research of asymmetric catalysis.This dissertation has developed some novel chiral molecules containing a 9,10-dihydrophenanthryl structure or a 9,9'-biphenanthryl structure,which were then evaluated on their applications in the asymmetric catalysis. In addition,the synthesis and applications of some novel amino acid-derived organocatalysts were also studied.The main content of the dissertation can be divided into four parts:(1) A novel model of tandem catalytic reaction was developed,in which the catalyst of the sequential step is a salt produced in situ in the prior step.The ortho-halogenated aromatic aldehydes could engage in the tandem Ullmann/pinacol reactions catalyzed by NiCl₂(PPh₃)₂.Using this tandem reaction,many compounds containing a trans-9,10-dihydroxy-9,10-dihydrophenanthryl structure were synthesized.These vicinal diols would be new cores ofchiral catalysts after resolving. Moreover,'one-pot' methods to prepare the derivatives of 9-phenanthrol and 9,10-phenanthrenequinone from the ortho-halogenated aromatic aldehydes were also developed.(2) The synthesis of trans-9,10-diamino-9,10-dihydrophenanthrene,a new vicinal diamine,was realized.The synthetic procedure employed a coupling reaction of a L-valine-derived diimine as a key step,and the two separated coupling products were converted to both the enantiomers of trans-9,10-diamino-9,10-dihydrophenanthrene each after multi-step transformations.A new Salen-type derivative was obtained by the condensation reaction of the salicalaldehyde and the enantiomeric pure vicinal diamine.This Salen-type compound was then tested as a ligand for the pinacol coupling reaction of benzaldehyde.(3) The synthesis of 9,9'-biphenanthryl compounds were detailed studied.Four 9,9'-biphenanthryl-10,10'-bis(oxazoline)s were synthesized using the 9-bromophenan-threne as a starting material.The synthetic procedure consists of 11 steps of reactions, and the total yields ranged from 22.5%to 26.4%.The bis(oxazoline)s were employed as ligands for the Friedel-Crafts alkylations of indoles with nitroalkenes,the selectivies were up to 85%ee at 0℃.The bis(oxazoline)s could be used in other reactions.Moreover,the synthesis,resolution,modification and transformation of 9,9'-biphenanthryl-10,10'-diol and 9,9'-biphenanthryl-10,10'-dicarboxylic acid were also studied.(4) Some novel amino acid-derived bifunctional organocatalysts were designed for the asymmetric Henry reactions.In the research,it was found that the amino group would be very weak nucleophilic and very weak alkaline if its a-carbon beared two phenyl substituents.A new organocatalyst containing a thiourea structure and a primary amino group was obtained.This bifunctional compound is now employed as a catalyst for some reactions.